Using similar dietary conditions in adult men (low sulfate, sulfur amino acid-deficient diet), nitrogen retention increased when sodium sulfate was added to the diet in an amount equivalent to that provided by additional methionine (Zezulka and Calloway, 1976).

Under these conditions, sulfate is probably used directly for PAPS biosynthesis, thereby sparing cysteine such that more of the cysteine is made available for protein synthesis and growth. A recent study in which lower levels of serum sulfate were detected when acetaminophen was given with glucosamine sulfate to normal adults